Propeller shaft variable pitch control



June 22, 1937- H. E. ROBERTS v PROPELLER SHAFT VARIABLE PITCH CONTROL Filed Dec. 28, 1955 Patented June 22, 1937 UNITED STATES PATENT OFFICE PEOPELLER SHAFT V PITCH This invention relates to improvements in controls adapted for use in connection with marine or aeroplane propellers and has for its principal object the provision of a means by which the 6 blades of a propeller may be controlled concerning the feathering of the same in the plane of rotation, and this is accomplished by longitudinal movement of the propeller shaft; in other words the propeller is directly controlled by the i shaft therefor, which is a more positive control than through various other elements associated with the propeller blades, as commonly used in many of the present types of control for this Other advantages of the invention will appear concurrently with the following detailed description, illustrated throughout the accompanying drawing, and more fully pointed out in the appended claim.

80 With reference to the drawing:

Figure 1 is a longitudinal section of the complete invention.

Figure 2 is an elevation of the propeller shaft end; Figure 3 is an end elevation of said shaft,

25 and Figure 4 is a bottom plan view thereof.

Figure 5 is a side elevation assembly, and broken in part as indicated.

Figure 6 is a section taken directly upon line 8-8 of Figure 2.

Figure 7 is a top plan view of one of the gears with propeller blade broken as shown.

I Figure 8 is an end elevation of the assembly shown in Figure 5.

Figure 9 is a sectional assembly with housing cap removed, and at the position of line 9-9 of I Figure 5.

In further disclosing the invention, it is to be understood that certain elements associated with 40 the same but not a part thereof will be desigwhile the invention proper will be characterized by the customary reference numerals.

The invention comprises housing I which is integral with hanger A and is preferably composed of bronze. The device is substantially supported by hanger A which is permanently secured to the bottom of a boat, or if applied to an aeroplane said hanger may be connected to 50 same in any approved manner. Housing i being of bronze a suitable bearing is thereby provided for sleeve member ll inasmuch as the same is adapted to rotate therein as clearly shown in Figure 1.

5 In Figures 5 and 8 it is observed that a suitable noted by consecutive letters of the alphabet,

cap B is provided for member II, and is detachably secured thereto by screws C where located. Sleeve member I4 and cap 3 are preferably composed of steel casting metal. Threaded apertures D are provided in member I! for the 6 accommodation of screws C.

The outstanding feature of the invention is the particular construction of the propeller shaft employed, consisting of shaft 2 which is perfectly round to the position of shoulder 3 there- 0 on, and in Figure 2 it is clear that said shaft is enlarged and forming thereby rectangular portion 4 with inwardly disposed teeth 5 and 0 positioned in opposite relation.

With particular reference to Figures 1 and 9 it is understood that segmental gears l and l are provided. Gear I is adapted to mesh with teeth I and is integral with propeller blade E. Gear 8 is adapted to mesh with teeth 0 and is integral with propeller blade F. Inasmuch as gears I and I are integral with the respective propeller blades and are composed of bronze a suitable bearing surface I is thereby provided as result of this particular combination of elements.

Each of gear members I and l are provided with a longitudinal counterbore and when assembled as in Figure 9 said counterbores are coaxially aligned by means of floating dowel pin Ill, thus blades E and F are at all times retained in perfect alignment in a stationary position and in the plane of rotation thereof.

Referring to Figure 1 it is clear that portion 4 of shaft 2 is shown in a neutral position, and with reference to a boat, blades E and F will be in a vertical position thus holding the boat at a standstill, and by longitudinally shifting shaft I in the direction of arrow G the boat will assume a forward motion due to the fact that simultaneous with this action gears l and 0 will be rotatably moved as result of their engagement with the respective teeth I and 0 of aforesaid shaft. To cause reverse action of the boat shaft 2 is longitudinally shifted in the direction of arrow H.

Sleeve member I4 is provided with reduced externally threaded shank H so as to detachabiy receive thrust collar II for obvious reasons. A suitable bearing surface is provided in member ll at the inner top and bottom thereof which is in the form of channel II, and so as to accommodate the sliding motion of portion 4 of shaft 2 as the same is normally actuated.

I claim:

In a propeller structure, a housing having a u cylindrical portion and an enlarged soeiret at one end thereof, a sleeve having a tubular shank rotatably received in the cylindrical portion of said housing with one end projecting therefrom and- 5 a cup-shaped portion at the other end of the shankseated in said socket and projecting outwardly therefrom, a removable cap for the outer end of the cup, a securing nut carried by the projecting end of said shank and abutting said hous- 10 ing. a shaft extending through said shank and 15 tions projecting laterally from the shaft and constituting abutment means for limiting sliding of the shaft and head inwardly of the cup, said shafts and propellers.

head having spaced side bars having their inner side faces provided with rack teeth and constituting opposed rack bars, propeller blades at opposite sides of said housing having stub shafts at their inner ends journaled between abutting portions of the cup and cap and having annular flanges at their inner ends disposed in abutting engagement with each other between the rack bars of said head, each flange having teeth forming a segmental gear on the flange, one gear meshing with one rack bar and the other gear meshing with the other rack bar, aligned axially extending bores being formed through the stub shafts, and a dowel pin fitting snugly in said bores and preventing lateral tilting of the stub HORATIO E. ROBERTS. 

